Spooling is a much more productive operation than spinning, because the yarn is spooled at a much higher linear velocity than in spinning, so that a limited number of spooling stations is capable of handling the yarn produced in a large number of spinning stations, for instance in a circuit-type spinning system producing yarn wound on a very large number of small size spools; these are then handled in the spooler, whose yarn is unraveled, freed from its defects and rewound on a smaller number of spools of larger size.
The moving in a spooler covers not only the full spools supplied by the spinners to the spooler and the empty tubes returned by the spooler to the spinner to form new spools, but also the non negligible number of irregular spools.
These irregular spools are generally tubes from which the wound yarn has not been picked up completely and from which the spooling unit is unable to recover further yarn by its own means, for instance because it tails to catch the end of skein to resume the unraveling process. The re-use of these irregular spools thus requires them to be recycled to the spools' setting-up station to recover their ends of skein and set them up for their unreeling in the spinning process. In order to feed them to the spinning process, the spools must In fact be set up with their ends of skein in a predetermined position, for instance inserted into the tube on which it is wound. The spooling station is thus capable of catching the ends of skein independently, and to launch their automatic spooling process without the aid of operators.
In the spooling circuit the spinner requires a considerable circulation of material to be moved and controlled: the empty tubes to be returned to the spinning process to rewind them into spools, the new spools to be set up for feeding to the spooler, and of the unraveled spools to be recirculated. In spoolers of a recent design the overall movement involves thousands of spools per hour.
For this reason the moving and normal handling of the machines are entrusted as far as possible to automatic devices, and the action of operators is limited to supervising and handling of malfunctions.
A technical solution for moving the spools and tubes enjoying considerable favor, for instance according to the patent FR 1,571,158 or U.S. Pat. No. 4,403,909, consists in moving them on trays, which are generally formed by a disc fitted with a spool or tube holding pin, or a central vertical peg capable of holding them in an upright position resting against a collar of a diameter larger than the tube. In this position the spool is subjected to essentially all the operations designed for the machine.
This setup allows the spools to be transferred and handled while essentially avoiding any undesirable soiling contact with the parts of the machine. The vehicle constituted by the tray also turns out to be most useful for the simultaneous handling of multiple batches of different yarns during the spooling process, because the spools can be differentiated based on their carrying tray and the latter can be addressed to the spooling stations specifically dedicated to them, according to the batches of yarn being processed.